Systems and Methods for Enabling Playback of Digital Content Using Electronic Tickets and Ticket Tokens Representing Grant of Access Rights

ABSTRACT

Systems and methods for accessing digital content using electronic tickets and ticket tokens in accordance with embodiments of the invention are disclosed. In one embodiment, a user device includes a processor, a network interface, and memory configured to store an electronic ticket, and a ticket token, and the processor is configured by an application to send a request for digital content, receive a ticket token from a merchant server, wherein the ticket token is generated by a DRM server and associated with an electronic ticket that enables playback of the requested digital content, send the ticket token to a DRM server, receive an electronic ticket that enables playback of requested digital content, request the digital content associated with the electronic ticket, and play back the requested digital content using the electronic ticket.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. 120 as acontinuation of U.S. patent application Ser. No. 14/567,994, entitled“Systems and Methods for Enabling Playback of Digital Content UsingElectronic Tickets and Ticket Tokens Representing Grant of AccessRights” to Ziskind et al., filed Dec. 11, 2014, which claims priorityunder 35 U.S.C. 120 as a continuation of U.S. patent application Ser.No. 13/436,900, entitled “Systems And Methods For Accessing DigitalContent Using Electronic Tickets And Ticket Tokens,” to Ziskind et al.,filed Mar. 31, 2012 and issued on Jul. 11, 2013 as U.S. Pat. No.8,918,908, which claims priority under 35 U.S.C. 119(e) to U.S.Provisional Application No. 61/583,807, entitled “Web PlayerRegistration With DRM Playback” to Ziskind et al., filed Jan. 6, 2012,the disclosures of which are incorporated herein by reference in theirentireties.

FIELD OF THE INVENTION

The present invention relates generally to digital rights management(DRM) systems and more specifically to authentication of user deviceswhen purchasing and requesting access to DRM protected multimediacontent.

BACKGROUND OF THE INVENTION

When a customer visits a movie theater, the process typically involvespurchasing a “ticket” at the ticket booth and having the ticket “torn”when the customer enters the theater. A ticket serves as a physicalproof of purchase for the right to view a particular movie. A ticket canchange possession from the purchaser to another customer and can be usedby either person. When a ticket is claimed by entering the theater andbeing torn, the ticket is thought to be redeemed by the customerpresenting the ticket and henceforth the viewing rights granted by theticket are owned by that customer.

In a digital multimedia playback system, viewing rights are generallygoverned by possession of physical media that contains digital content.When the content is not tied to physical media, such as when digitalcontent is streamed over a network, a digital rights management (DRM)system is often used to restrict access to the content. Such systemstypically involve user accounts and associating purchased content with auser account. A user device may be registered to a user account and thenhave access to the content purchased under that user account.

SUMMARY OF THE INVENTION

Systems and methods for accessing digital content using electronictickets and ticket tokens in accordance with embodiments of theinvention are disclosed. In one embodiment, a user device includes aprocessor, a network interface, and memory configured to store anelectronic ticket, and a ticket token, and the processor is configuredby an application to send a request for digital content, receive aticket token from a merchant server, wherein the ticket token isgenerated by a DRM server and associated with an electronic ticket thatenables playback of the requested digital content, send the ticket tokento a DRM server, receive an electronic ticket that enables playback ofrequested digital content, request the digital content associated withthe electronic ticket, and play back the requested digital content usingthe electronic ticket.

In a further embodiment, the electronic ticket includes a torn status.

In another embodiment, the electronic ticket is an XML file.

In a still further embodiment, the electronic ticket identifies thepurchased digital content.

In still another embodiment, the electronic ticket includes acharacteristic of the purchased content selected from the group ofinformation identifying the content that was purchased, a licenseindicating how the content can be played back, a purchase price, amerchant transaction identifier, the identification of a customer whopurchased the ticket, and the identification of a customer owning theticket.

In a yet further embodiment, the electronic ticket is associated withcryptographic data that can be used to access the digital content towhich the electronic ticket refers.

In yet another embodiment, the ticket token references the electronicticket, a customer, and the requested digital content.

In a further embodiment again, the processor is further configured toreceive access information for the digital content.

In another embodiment again, the access information includes at leastone piece of information selected from the group of a top level index ofthe digital content, an identifier for the digital content, andcryptographic data that can be used to access the digital content.

In a further additional embodiment, the electronic ticket is embedded inthe header of a multimedia file.

Another additional embodiment includes sending a request for digitalcontent from a user device to a merchant server, receiving a tickettoken from the merchant server using the user device, where the tickettoken is generated by a DRM server and associated with an electronicticket that enables playback of the requested digital content, sendingthe ticket token to a DRM server using the user device, receiving theelectronic ticket from the DRM server using the user device, downloadingthe digital content associated with the electronic ticket from a contentserver using the user device, and playing back the requested digitalcontent.

In a still yet further embodiment, the electronic ticket includes a tornstatus.

In still yet another embodiment, the electronic ticket is an XML file.

In a still further embodiment again, the electronic ticket identifiesthe purchased digital content.

In still another embodiment again, the electronic ticket includes acharacteristic of the purchased content selected from the group ofinformation identifying the content that was purchased, a licenseindicating how the content can be played back, a purchase price, amerchant transaction identifier, the identification of a customer whopurchased the ticket, and the identification of a customer owning theticket.

In a still further additional embodiment, the electronic ticket isassociated with cryptographic data that can be used to access thedigital content to which the electronic ticket refers.

In still another additional embodiment, the ticket token references theelectronic ticket, a customer, and the requested digital content.

A yet further embodiment again includes receiving access information forthe digital content.

In yet another embodiment again, the access information includes atleast one piece of information selected from the group of a top levelindex of the digital content, an identifier for the digital content, andcryptographic data that can be used to access the content.

In a yet further additional embodiment, the electronic ticket isembedded in the header of a multimedia file.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system-level overview illustrating a DRM and contentdistribution system in accordance with an embodiment of the invention.

FIG. 2 is a flow chart illustrating a process for providing a userdevice with access to digital content using an electronic ticket andticket token, in accordance with an embodiment of the invention.

FIG. 2A is a flow chart illustrating a process for providing a userdevice with access to digital content using an electronic ticket andticket token on a user device, in accordance with an embodiment of theinvention.

FIG. 2B is a flow chart illustrating a process for providing a userdevice with access to digital content using an electronic ticket andticket token on a DRM server, in accordance with an embodiment of theinvention.

FIG. 3 conceptually illustrates a user device, which stores anelectronic ticket and ticket token in memory, in accordance with anembodiment of the invention.

FIG. 4 conceptually illustrates a DRM server, which stores electronictickets and ticket tokens in memory, in accordance with an embodiment ofthe invention.

DETAILED DISCLOSURE OF THE INVENTION

Turning now to the drawings, systems and methods for accessing digitalcontent using electronic tickets and ticket tokens are illustrated. Inmany embodiments, a user device can communicate with merchant servers,digital rights management (DRM) servers, and content servers to requestaccess to and play back digital content. A user device may be configuredwith a web browser, web application, or other application that providesa user interface to a customer. The interface typically displays thedigital content available from a merchant and is populated with datafrom the merchant server.

In many embodiments, a user device can purchase the right to accessdigital content from a merchant server. However, the user device obtainsthe cryptographic information used to access the purchased contentdirectly from a DRM server. In several embodiments, a merchant serverrequests that the DRM server issue the right to access a piece ofdigital content to one of its customers. In response to the request, theDRM server generates an electronic ticket. The DRM server can alsogenerate a ticket token associated with the electronic ticket at thattime and/or when a user device requests playback of the content via themerchant website. The electronic ticket is evidence of the right of auser device registered with the DRM server to playback DRM protectedcontent. The ticket token is a temporary credential that can be used toobtain the electronic ticket from the DRM server by a playback devicethat is registered with the DRM server and/or to obtain cryptographicinformation enabling playback of the content from the DRM server. Inmany instances the DRM server cannot authenticate the user device thatis purchasing the content from the merchant server. The DRM server canprovide the ticket token to the merchant server, which passes the tickettoken to the user device used to purchase the content. Provided the userdevice or another user device onto which the token is loaded isregistered with the DRM server, the user device can provide the tickettoken to the DRM server and obtain the electronic ticket and anycryptographic information needed to access the purchased content. Atwhich point, the user device can request the DRM protected content fromthe content server and commence playback using the cryptographicinformation. The use of electronic tickets, and ticket tokens toauthenticate the right of a user device to playback digital content inaccordance with embodiments of the invention is discussed further below.

System Architecture

A system including user devices that can communicate with merchantservers, DRM servers and content servers to access digital content inaccordance with an embodiment of the invention is illustrated in FIG. 1.The system 10 includes a number of different types of user device 12that each has the capability to request digital content over a network.The user devices 12 communicate with a merchant server 14, digitalrights management (DRM) server 16 and content server 18 over a networksuch as the Internet 20. In a number of embodiments, merchant server 14provides a “store front” like interface accessible to customers via aweb browser or other application on their user device 12. The DRM server16 can be used to authenticate user devices 12 and provide cryptographicinformation used to access digital content. In several embodiments, thecontent server 18 is a server that can deliver digital content to theuser devices 12. The content can be downloaded and/or streamed by theuser devices 12.

An electronic ticket issued by the DRM server in response to thepurchase of content that serves as a representation of the purchase canbe used to facilitate access of the purchased content in a coordinatedfashion among the user device 12, merchant server 14, DRM server 16, andcontent server 18. In many embodiments, however, the merchant server 14is unable to authenticate the user device 12 that purchased the contentto the DRM server 16. Accordingly, the DRM server 16 issues a tickettoken to the merchant server 14 that acts as a temporary credential. Inseveral embodiments, the ticket token is a single use credential thatcan be utilized by a user device that authenticates itself to the DRMserver to obtain the electronic ticket and/or cryptographic informationenabling playback of the content. In a number of embodiments, the tickettoken is generated when the user device requests playback of the contentand expires within a predetermined period of time. In other embodiments,the ticket token, is generated when the user device purchases thecontent.

The merchant server 14 can provide the ticket token to the user device12 that purchased the content. Provided the user device 12 is registeredwith the DRM server 16, the user device 12 can authenticate itself tothe DRM server and exchange the ticket token for the electronic ticketthat evidences the user device's right to access the purchased content.Where the user device 12 that purchased the content is not authorized toparticipate within the DRM system administered by the DRM server 16, theticket token can be transferred to a device that is capable ofparticipating within the DRM system. In embodiments where the DRM serverregisters user devices with user accounts, DRM system can provide anelectronic ticket to a registered user device and can associate theelectronic ticket with the user account to which the device isregistered. In this way, other user devices registered to the useraccount can request access to the purchased content following theinitial exchange of the ticket token for the electronic ticket. Ininstances where the user device has previously requested playback of thecontent, the user device can be in possession of the electronic ticket.When the user device again requests playback of the content via themerchant website (for example by streaming), the merchant can providethe electronic ticket to the DRM server to obtain a ticket token. Theuser device can then use the ticket token to access the content in themanner outlined above and the DRM server can authenticate that theelectronic ticket provided by the merchant server is associated with theuser device attempting to play back the content prior to providingcryptographic information enabling play back of the content to the userdevice.

Although a specific architecture is shown in FIG. 1 any of a variety ofarchitectures can be utilized that enable user devices to securelyaccess digital content using electronic tickets and ticket tokens inaccordance with embodiments of the invention. For example, each of theservers illustrated in FIG. 1 can be a server system comprising multipleload balanced servers and/or servers that perform different functions.In addition, the functions of the servers illustrated in FIG. 1 can becombined and/or divided amongst different servers and server systems inaccordance with embodiments of the invention. Electronic tickets, tickettokens, and the use of tickets to access digital content in accordancewith embodiments of the invention are discussed further below.

Electronic Tickets

An electronic ticket represents the purchased right to access a piece ofdigital content. Electronic tickets can also be used to represent theright to playback any DRM protected content including free content thatis not capable of being freely distributed and content played back undera subscription agreement. Accordingly, references to purchased contentcan be considered to encompass more than just requests to access DRMprotected content that involve a direct payment and can extend to anyrequest for access to content. An electronic ticket can be a string,binary data, or other electronic representation of information thatincludes at least a unique identifier for the content with which theelectronic ticket is associated.

Electronic tickets typically remain valid for the life of the purchase.When the purchase is a rental of the content, the ticket may be expiredafter the rental period. A ticket can initially be in a conceptually“untorn” state before it is used to access content. It is not yetassociated with any particular user account and/or user device, and canbe transferred from the purchaser to any other user, for instance as agift. The electronic ticket may be “torn” and associated with a useraccount and/or user device that then holds the exclusive rights grantedby that ticket. Whether a DRM system associates an electronic ticketwith a user account or a user device can depend on whether the DRMsystem grants access rights on a device or user basis. Thereafter, thatuser account and/or user device is considered the owner or holder of theticket. An electronic ticket may be torn, for example, when it is usedfor the first time to access content or in response to a user deviceexchanging a ticket token for an electronic ticket (see discussionbelow). An electronic ticket's torn or untorn status can be indicated bya variety of methods including (but not limited to) a field within theticket or an associated field in a database where the ticket is stored.

An electronic ticket may be expressed in a variety of formats that canstore the associated information. One suitable format is ExtensibleMarkup Language (XML) defined in the XML 1.0 Specification by the WorldWide Web Consortium (W3C) of Cambridge, Mass. and relatedspecifications. XML specifies a textual data format for documents to beboth human-readable and machine-readable.

In many embodiments of the invention, an electronic ticket may contain,reference, or be associated with some characteristics of the purchase itrepresents. Characteristics can include (but are limited to) the contentthat was purchased, the license describing how the content can be played(high definition or standard definition, rental or purchase, download orstreaming, etc.), the purchase price, the merchant transactionidentifier (ID), the customer who purchased the ticket, the customerowning the ticket if the ticket is torn. Cryptographic information thatcan be used to decode or decrypt the digital content may also beassociated with a ticket. The characteristics or cryptographicinformation may be stored as part of the electronic ticket or the ticketmay have a pointer or identifier to where the information may be found.

Ticket Token

A ticket token can be generated and associated with an electronic ticketas a temporary credential, which can be exchanged for an electronicticket by a user device that is registered with a DRM system. In manyembodiments, a merchant server requests a ticket token from a DRM serverwhen a user request playback of content. In several embodiments, themerchant server requests a ticket token from the server when the userpurchases content. The request may contain information such as (but notlimited to) a content identifier, a merchant identifier, an account linkidentifier, a license identifier, a stream identifier, a transactionidentifier, currency, and/or price. The ticket token that is returnedmay reference the electronic ticket, customer, and current contentrequest. The first time the user device requests playback, the userdevice can exchange the ticket token for an electronic ticket. After theuser device has obtained the electronic ticket, a further playbackrequest can identify the electronic ticket and a DRM server can issue aticket token that is used to authenticate that the user deviceattempting to playback the content is registered to the user accountwith which the electronic tickets is associated.

In several embodiments, the merchant server provides the ticket token toa user device only after the user device or a user account enabled onthe user device is authenticated by the merchant server. The DRM servercan issue the ticket token without authenticating the user device. Theauthentication occurs when the ticket token is used to request playbackof the content and/or exchanged for the electronic ticket by a userdevice. In many embodiments, the DRM server may determine when a sessionis complete and expire the token, or expire the token after a certainamount of time has passed. Moreover, a token can typically only be usedonce. Methods for granting access to DRM protected content usingelectronic tickets and associated ticket tokens in accordance withembodiments of the invention are discussed further below.

Obtaining a Ticket and Ticket Token to Facilitate Playback

Typically a customer will buy or otherwise request access to digitalcontent on a merchant's web site or through some other type of interfacethat shows the merchant's digital content offerings. The customer mayuse a personal computer with a web browser application, a user devicewith an on-screen interface, or other interactive user device to viewthe merchant's offerings. The customer typically has an account with themerchant and logs in using the account, or first creates a new accountif there is no existing account. The purchased content can be viewed inthe future (i.e., the associated electronic ticket is untorn) orimmediately played back. In several embodiments, the content is streamedand/or viewed while it is being downloaded.

In many embodiments, the process of purchasing and playing back contentinvolves a merchant obtaining a ticket token from a DRM server. A userdevice that obtains the ticket token can exchange it with the DRM serverfor an electronic ticket evidencing the user device's right to play backthe purchased content and cryptographic information necessary to playback the purchased content. A process 100 for granting user devices withaccess to digital content purchased via a merchant using an electronicticket and an associated electronic token in accordance with anembodiment of the invention is shown in FIG. 2.

A DRM server authenticates (102) a merchant server. Authentication mayinvolve establishing a certain level of identification and trust betweenthe merchant server and the DRM server and/or the DRM system to whichthe DRM server belongs.

A user device sends (104) a request for digital content to a merchantserver.

The merchant server sends (106) a request for a ticket token to a DRMserver. If it is a new purchase, an electronic ticket may not yet existand the merchant server may also request that a new electronic ticket becreated to represent the purchase. In several embodiments of theinvention, the request may also include information to be associatedwith the purchase. The information may include (but is not limited to) acontent identifier, merchant link identifier, account link identifier,license identifier, stream identifier, transaction identifier, currency,and/or price.

The DRM server generates (108) a ticket token and associates the tokenwith the electronic ticket that represents the purchase. If it is a newpurchase, the DRM server creates a new electronic ticket. If playback isrequested of content that was previously purchased and played back by auser device registered to a user's account with the DRM server, theticket token is associated with the existing electronic ticket. Invarious embodiments of the invention, the digital content may betransferring via a streaming protocol for immediate viewing ordownloaded at a later time to be viewed in a disconnected playback mode(i.e., not in immediate communication with a server). If streamedimmediately, the electronic ticket may be “torn” immediately. If thecontent is to be downloaded at a later time, the electronic ticket maybe “untorn” and retain the ability to be transferred to another customerbefore being “torn” and associated with that customer's account. Theelectronic ticket may be stored on a user device, deleted from thedevice when playback is requested, and embedded in a container file withthe content for disconnected playback as will be discussed furtherbelow.

The DRM server sends (110) the ticket token to the merchant server. Ifthe merchant server does not yet have the electronic ticket (e.g., for anew purchase), the DRM server can also send the electronic ticket. Inmany embodiments, the merchant server stores the electronic ticket forfuture reference.

The merchant server sends (112) the ticket token to the user device.

The user device sends (114) the ticket token to the DRM server. In thecommunication with the DRM server, the user device may also sendinformation about the customer and/or the device that identifies ordescribes the customer and/or device. For example, the user device maybe authenticated with the DRM server. Authentication may include thedevice identifying itself as registered to a specific user account. Theuser account may be the same the account the consumer or user deviceholds with the merchant server, or (more typically) a separate accountthat the consumer or user device holds with the DRM system to which theDRM server belongs.

In many embodiments of the invention, the device may send informationthat identifies the brand and model of the device, or the graphics andaudio capabilities of the device (e.g., high definition, multi-channelaudio, MPEG4 decoding). The information can be used to help authenticatethe device to the DRM system and determine the appropriate format of thecontent to provide to the device. Systems and processes for collectinginformation about a user device and representing the information using adevice match data token include those disclosed in U.S. patentapplication Ser. No. 13/339,315 entitled “Binding of CryptographicContent Using Unique Device Characteristics with Server Heuristics,” thedisclosure of which is hereby incorporated by reference in its entirety.

The DRM server validates (116) the ticket token, e.g., by checking thatthe token has not yet been used and is not expired. The DRM server usesthe ticket token to determine the electronic ticket to which it refersand customer information for the customer who sent the request.

The DRM server may associate (118) the electronic ticket with thecustomer's user account and register the user device to the user accountif they are not already so registered, using the customer informationassociated with the ticket token and device match data it may havereceived from the user device.

In many embodiments of the invention, the DRM server may also verify theplay request according to certain rules using the ticket token and/or adevice match data token. For example, the DRM server may enforceconcurrency and device rules on the playback of content. A concurrencyrule may stipulate that only one device on the user account can playback any content at a time, or that a specific piece of content may onlybe played on one device at a time. Device rules may include limitinghigh definition content to user devices such as set-top boxes connectedto television displays. A device match data token identifies the type ofdevice so the DRM server can look up the device type to determine theappropriate format of content.

In many embodiments of the invention, the electronic ticket and/or theticket token contain information to identify the license under which thecontent can be played. The DRM server can use the ticket information toretrieve the license information and generate or retrieve accessinformation that the user device can use to access or decrypt therequested content. Access information can include (but is not limitedto) a top level index file of the digital content, an identifier orlocation pointer for the digital content, and/or cryptographic data thatcan be used to access and/or decrypt the content. In several embodimentsof the invention, a top level index file describes the location andcontent of container files containing streams of media that can beutilized by the playback device to stream and playback content. Inadaptive bitrate streaming systems, the top level index file typicallyreferences the alternative streams that the playback device can switchbetween. Systems and methods for automatically generating top levelindex files for use in adaptive bitrate stream include those disclosedin U.S. patent application Ser. No. 13/341,789 entitled “Systems andMethods for Automatically Generating Top Level Index Files,” filed onDec. 30, 2011, the disclosure of which is hereby incorporated byreference in its entirety.

The DRM server sends (120) the electronic ticket to the user device. Inseveral embodiments, the electronic ticket embedded in another file. Theticket may be embedded in a file that also contains the content that wasrequested, e.g., in the header of a multimedia container file. In manyembodiments, the DRM server also sends the access information that isused to access or play back the content that was requested. The DRMserver invalidates the token by expiring (122) it.

Using the received electronic ticket and access information, the userdevice can play back the requested content via download or streaming. Inmany embodiments of the invention, the content is hosted on a contentserver that is accessible to the user device over a network. The userdevice may request the content from the content server. The content maybe downloaded and played (124) during download or after downloading iscomplete, or streamed and played while being transferred to the userdevice. The user device may send a signal such as a “heartbeat” to theDRM server to let the server know that it is currently playing backcontent and/or the position in the file that is being played back. TheDRM server can use this information for functions such as providing aresume feature so that the customer can stop playback and restart at thesame position on the same or a different user device.

Although a specific process is illustrated in FIG. 2, any of a varietyof processes for utilizing an electronic ticket and a ticket token thatreferences the electronic ticket for providing a user device with accessto purchased digital content can be utilized in accordance withembodiments of the invention.

Processes similar to the process illustrated in FIG. 2 may beimplemented by configuring user devices and servers to exchangeelectronic tickets and ticket tokens. A generalized process 130 forusing a user device to obtain access to digital content purchased via amerchant using an electronic ticket and an associated electronic tokenin accordance with an embodiment of the invention is shown in FIG. 2A. Acustomer uses a user device to purchase (132) content or request theplayback of purchased content. The user device receives (134) a tickettoken from a merchant server. The user device sends (136) the tickettoken to a DRM server in a request for access to digital content. Theuser device receives (138) an electronic ticket that is referenced by orotherwise associated with the ticket token and access information forthe digital content from the DRM server. Using the electronic ticket andaccess information, the user device receives and plays back (140) therequested content. In many embodiments of the invention, the content ishosted on a content server that is accessible to the user device over anetwork. Although a specific process is illustrated in FIG. 2A, any of avariety of processes for utilizing an electronic ticket and a tickettoken that references the electronic ticket for providing a user devicewith access to purchased digital content can be utilized in accordancewith embodiments of the invention.

A generalized process 150 for using a DRM server to provide a userdevice with access to digital content purchased via a merchant using anelectronic ticket and an associated electronic token in accordance withan embodiment of the invention is shown in FIG. 2B. The DRM serverauthenticates (152) a merchant server. The DRM server receives (154) arequest for a ticket token from a merchant server. The DRM servergenerates (156) a ticket token and associates the token with anelectronic ticket. If there is no preexisting ticket (e.g., for a newpurchase), the DRM server also creates the electronic ticket. The DRMserver sends (158) the ticket token to the merchant server for deliveryto a user device. The DRM server authenticates (160) a user device. TheDRM server receives (162) the ticket token in a request for access todigital content from the user device and validates (164) the token. Ifuser account information is provided, the DRM server associates (166)the electronic ticket with the user account. The DRM server sends (168)the electronic ticket referenced by or otherwise associated with theticket token to the user device with access information for the digitalcontent that was requested. The DRM server expires (170) the tickettoken. Although a specific process is illustrated in FIG. 2B, any of avariety of processes for utilizing an electronic ticket and a tickettoken that references the electronic ticket for providing a user devicewith access to purchased digital content can be utilized in accordancewith embodiments of the invention. User devices and DRM servers that canutilize electronic tickets and ticket tokens in accordance withembodiments of the invention are discussed further below.

User Devices

In many embodiments of the invention, an electronic ticket is stored ona playback device to enable the user device to access content through aDRM system using the electronic ticket. A user device configured toaccess purchased content using electronic tickets in accordance with anembodiment of the invention is shown in FIG. 3. The playback device 30includes a processor 32, memory 34, and a network interface 35. In theillustrated embodiment, the electronic tickets 36 and ticket tokens 38can be stored in memory. Typically, the memory is non-volatile memory toprovide persistent storage of the electronic tickets 36 and the tickettokens 38. In a number of embodiments, the electronic ticket 38 may becontained inside a container file together with the content to which itrefers. In several embodiments, a ticket may be stored on a purchaser'suser device after purchase, may be transferred to another device ifgiven as a gift, and may be deleted in its isolated form (i.e., outsidea container file) from the device when it is torn. Tickets are typicallytreated this way in a disconnected playback mode. In severalembodiments, a client application 39 configures the user device tocommunicate with the merchant server to purchase content and obtainticket tokens. The client application 39 also configures the user deviceto authentic itself with a DRM server and to request cryptographicinformation to play back content using a ticket token and/or exchangethe ticket token for an electronic ticket. Although a specific userdevice architecture is illustrated in FIG. 3, any of a variety ofarchitectures that are capable of managing interactions with servers andplayback of digital content in the manner outlined above can be utilizedin accordance with embodiments of the invention can

DRM Servers

In many embodiments of the invention, electronic tickets and tickettokens may be stored on a merchant server or a DRM server (e.g., in adatabase) for reference, to track purchases, and to provide user deviceswith access to content. A merchant or DRM server may look up anelectronic ticket using fields such as (but not limited to) a customeremail address, merchant identifier, content identifier, or merchanttransaction identifier. A DRM server configured to issue electronictickets and ticket tokens and to provide cryptographic informationenabling playback of DRM protected content in accordance with anembodiment of the invention is shown in FIG. 4. The DRM server includesa processor 52 and memory 54. In the illustrated embodiment, the memory54 includes multiple electronic tickets 56 and ticket tokens 58. As isdiscussed above, the DRM server can be configured by DRM serverapplication software 59 to manage the generation of electronic tickets,the issuance of ticket tokens associated with the electronic tickets,and the association of electronic tickets with users and/or userdevices. In addition, the DRM server application software 59 can managethe issuance of cryptographic information (not shown) to playbackdevices that are authorized to playback content, the authorization ofwhich is evidenced by an electronic ticket.

Although the description above contains many specificities, these shouldnot be construed as limiting the scope of the invention but as merelyproviding illustrations of some of the presently preferred embodimentsof the invention. Various other embodiments are possible within itsscope. Accordingly, the scope of the invention should be determined notby the embodiments illustrated, but by the appended claims and theirequivalents.

What is claimed is:
 1. A user device, comprising: a processor; a networkinterface; and memory configured to store: an electronic ticket, and aticket token; wherein the processor is configured by an application to:send a request for digital content; receive a ticket token from amerchant server, wherein the ticket token is generated by a DRM serverand associated with an electronic ticket that enables playback of therequested digital content; send the ticket token to a DRM server;receive an electronic ticket that enables playback of requested digitalcontent; request the digital content associated with the electronicticket; and play back the requested digital content using the electronicticket.
 2. The user device of claim 1, wherein the electronic ticketincludes a torn status.
 3. The user device of claim 1, wherein theelectronic ticket is an XML file.
 4. The user device of claim 1, whereinthe electronic ticket identifies the purchased digital content.
 5. Theuser device of claim 4, wherein the electronic ticket includes acharacteristic of the purchased content selected from the groupconsisting of: information identifying the content that was purchased, alicense indicating how the content can be played back, a purchase price,a merchant transaction identifier, the identification of a customer whopurchased the ticket, and the identification of a customer owning theticket.
 6. The user device of claim 1, wherein the electronic ticket isassociated with cryptographic data that can be used to access thedigital content to which the electronic ticket refers.
 7. The userdevice of claim 1, wherein the ticket token references the electronicticket, a customer, and the requested digital content.
 8. The userdevice of claim 1, wherein the processor is further configured toreceive access information for the digital content.
 9. The user deviceof claim 8, wherein the access information includes at least one pieceof information selected from the group consisting of: a top level indexof the digital content, an identifier for the digital content, andcryptographic data that can be used to access the digital content. 10.The user device of claim 1, wherein the electronic ticket is embedded inthe header of a multimedia file.
 11. A method for enabling playback ofdigital content on a user device using an electronic ticket and a tickettoken, the method comprising: sending a request for digital content froma user device to a merchant server; receiving a ticket token from themerchant server using the user device, wherein the ticket token isgenerated by a DRM server and associated with an electronic ticket thatenables playback of the requested digital content; sending the tickettoken to a DRM server using the user device; receiving the electronicticket from the DRM server using the user device; downloading thedigital content associated with the electronic ticket from a contentserver using the user device; and playing back the requested digitalcontent.
 12. The method of claim 11, wherein the electronic ticketincludes a torn status.
 13. The method of claim 11, wherein theelectronic ticket is an XML file.
 14. The method of claim 11, whereinthe electronic ticket identifies the purchased digital content.
 15. Themethod of claim 14, wherein the electronic ticket includes acharacteristic of the purchased content selected from the groupconsisting of: information identifying the content that was purchased, alicense indicating how the content can be played back, a purchase price,a merchant transaction identifier, the identification of a customer whopurchased the ticket, and the identification of a customer owning theticket
 16. The method of claim 11, wherein the electronic ticket isassociated with cryptographic data that can be used to access thedigital content to which the electronic ticket refers.
 17. The method ofclaim 11, wherein the ticket token references the electronic ticket, acustomer, and the requested digital content.
 18. The method of claim 11,further comprising receiving access information for the digital content.19. The method of claim 18, wherein the access information includes atleast one piece of information selected from the group consisting of: atop level index of the digital content, an identifier for the digitalcontent, and cryptographic data that can be used to access the content.20. The method of claim 11, wherein the electronic ticket is embedded inthe header of a multimedia file.